title: The impact of highly hydrophobic material on the structure of transferrin and its ability to bind iron.
abstract: Transferrin is a blood-plasma glycoprotein, which is responsible for ferric-ion delivery and which functions as the most important ferric pool in the body. The reversible complexation process of Fe(3+) ions is associated with conformational changes of the three-dimensional structure of the transferrin. This conformational dynamics is attributed to a partial unfolding of the N-lobe of the protein and could be described as a transition between the holo to the apo forms of the transferrin. The aim of the present work is to demonstrate the unprecedented ability of the transferrin to solubilize various polycyclic aromatic hydrocarbons in physiological solution and to explore the impact of these materials on the structure and functionality of the transferrin. The synthesis and characterization of novel materials, consisting of complexes between human transferrin and hydrophobic high-carbon-content compounds, is reported here for the first time. Furthermore, it is shown that the preparation of these complexes from holo-transferrin leads to an irreversible loss of the ferric ions from the protein. Analytical studies of these novel complexes may shed a light on the mechanism by which transferrin could lose its ability to bind and thus to transport and store iron. These findings clearly demonstrate a possible damaging impact of various hydrophobic pollutants, which can enter an organism by inhalation or ingestion, on the functionality of the transferrin.
authors.affiliation: School of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 69978, Israel. eyal.drg@gmail.com
authors.forename: E
authors.initials: E
authors.lastname: Drug
authors.forename: L
authors.initials: L
authors.lastname: Fadeev
authors.forename: M
authors.initials: M
authors.lastname: Gozin
mesh_terms: D002942:Circular Dichroism; D004785:Environmental Pollutants / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D007501:Iron / Q000378:metabolism*; D011084:Polycyclic Aromatic Hydrocarbons / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D011487:Protein Conformation; D017510:Protein Folding; D012995:Solubility; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D013329:Structure-Activity Relationship; D014168:Transferrin / Q000737:chemistry / Q000378:metabolism*
chemical_list: D004785:Environmental Pollutants; D011084:Polycyclic Aromatic Hydrocarbons; D014168:Transferrin; D007501:Iron